Recently, there have been increased demands for a large scale monitoring system that analyzes a plurality of camera videos in realtime to detect a moving object such as a person or an object, and automatically alerts an administrator. For example, there has been considered a case in which when a person has entered into an entry prohibited area, even though an administrator does not see a video, an alert is automatically issued to allow the administrator to know the intrusion.
In such a monitoring system, video data is transmitted from each network camera (IP (Internet Protocol) camera) to a monitoring center (also called a monitoring base) that performs monitoring. The video data is normally encoded by a video data compression standard such as an MPEG (Moving Picture Experts Group)-4 or an MPEG-2, and is transmitted from the network camera to the monitoring center.
According to a compression standard of high compression such as an MPEG-4 standard (ISO/IEC 14496 or ITU-T H.264) or an MPEG-2 standard (ISO/IEC 13818) often used in a large scale monitoring system, compression processing is performed by a technology such as inter-frame prediction. Therefore, when the above-described standard is compared with a standard such as a Motion JPEG (ISO/IEC 29199-3:2010), the above-described standard has characteristics that an operation amount during decoding is further increased and a load of a CPU (Central Processing Unit) during decoding is increased.
Japanese Laid-open Patent Publication No. 2013-125304 (Patent Literature 1) discloses a technique for shortening a video analysis time. In detail, Patent Literature 1 discloses a parallel video analysis device that obtains a plurality of image frames located at any integral multiple of a predetermined thinned-out image frame interval from an image frame at the beginning of video data. Furthermore, the parallel video analysis device starts detection processing of event information in the video data from each image frame at the thinned-out image frame interval temporally in parallel.
Furthermore, a method for searching subtitles in a video and reducing a processing amount is disclosed in Japanese Laid-open Patent Publication No. 2009-159260.
Furthermore, a method for calculating the number of TS packets included in respective frames as a frame data quantity of the frame according to a frame start position included in inputted TS packets of video communication, and determining a frame type according to a large/small relationships between the frame data quantities of the frames is disclosed in International Publication No. 2009/025357.
In addition, an example of a large scale video processing technologies is disclosed in the URL (http://jpn.nec.com/press/201209/20120904_01.html: press release issued by NEC dated Sep. 4, 2012).